The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
Moving Picture Experts Group (MPEG) and Video Coding Experts Group (VCEG) together stepped ahead of the existing MPEG-4 Part 2 and H.263 standard methods to develop a different video compression standard. The new standard is called H.264/AVC (Advanced Video Coding) and was released simultaneously as MPEG-4 Part 10 AVC and ITU-T Recommendation H.264.
In the H.264/AVC standard, an intra/inter prediction process is performed, in units of a block having various shapes of subblocks, to generate a residual signal. A transform and a quantization step are performed on the generated residual block to reduce the number of bits of the generated residual block before entering an encoding operation. A macroblock encoding operation, as viewed from the encoder side, includes dividing an input image into 16×16 macroblock units, performing a prediction on each macroblock (in the level of a subblock sized according to the inter/intra mode) to generate a residual block, processing the generated residual block with an integer transform based on a discrete cosine transform (DCT) in 4×4 or 8×8 unit to generate frequency coefficients, and quantizing the frequency coefficients according to a quantization parameter (QP). Afterwards, blocking artifacts resulting from the transform and quantization process, may be reduced by using a deblocking filtering.
In order to remove the blocking artifacts, an algorithm is used to improve the subjective/objective performance of the image by performing a more efficient deblocking filtering.